Garbage grinder



Jan. 16, 1962 Filed July. 6 1959 2 Sheets-Sheet 1 5i l w \W a I f; 2 .5: l 7 9 flw w WWW 7 0 od w 5 -1 l o M i W @M 1. H7 a Zflh KN 3L INVENTOR. ea/ye Q Sherman 147 ORA/f Y5.

Jan. 16, 1962 Filed July 6, 1959 G. O. SHERMAN GARBAGE GRINDER 2 Sheets-Sheet 2 INVENTOR. flea/ye 0. 5/72/7770 ilnited rates ipatent 3,017,125 GARBAGE GRINDER George 0. Sherman, Prairie Village, Karts, assign-or to 'I he Saivajor (lompany, Kansas City, Mo., a corporation of Missouri Filed July 6, I359, Ser. No. 825,195 12 Claims. (Cl. 241-46) Although waste disposal units of the type referred to above have been employed to advantage for some time in houses as well as commercial kitchens and processing plants, the same have not been entirely satisfactory, especially where a relatively heavy load is placed on the equipment by direction of a large quantity of waste materials into the grinding apparatus per unit of time. Under such conditions of heavy usage, the sewer line in certain instances becomes clogged with the pulverized waste products, either because the same are not adequately ground within the machine or a larger amount of ground materials is forced into the sewer line than the latter is capable of handling. Clogging of the sewer pipe causes the liquid and pulverized materials to back up in the grinding unit, thereby producing considerable pressure in the lower discharge chamber of the grinder housing.

Inasmuch as garbage disposal units of the type referred to above employ a motor having a shaft extending into the interior of the grinder housing to rotate a grinding rotor, it can be recognized that seal means have heretofore been provided between the rotating shaft and the opening therefor in the housing to prevent the liquid and pulverized garbage from passing out of the housing through the shaft opening rather than through the sewer discharge outlet.

In those instances where the sewer line becomes clogged with ground material, and backup of the liquid and pulverized products occurs within the lower chamber of the grinder housing, considerable fluid pressure is placed on the seal by virtue of the fact that the grinding rotor produces a downward thrust of the liquid and ground products against the liquid seal.

Although the shaft seals are usually effective in preventing liquid from passing outwardly from the grinder housing through the shaft opening during normal operation of the machine, when extreme pressures are placed on such seals during clogging of the sewer pipes, in most cases, the seals give way and the liquid and pulverized materials flow downwardly along the shaft and into the interior of the motor. Under these conditions, the motor soon burns out and it is necessary to replace the same in order to repair the grinding unit.

Another difficulty encountered in prior grinders utilizing a seal around the motor shaft is the fact that most of the seals are of the type which require liquid normally present within the housing to lubricate the seal and, therefore, when operators of the grinding machine fail to turn on the water in conjunction with direction of waste products into the machine, the seal oftentimes burns out because of lack of lubrication.

It is, therefore, the most important object of the present invention to provide a machine for grinding waste products of a type as set forth above but which has no need 3,917,125 Patented Jan. 16, 1962 for the conventional seal around the motor shaft to protect the motor.

It is a further important object of the invention to provide a machine of the character referred to wherein the unit housing, as well as the grinding rotor disposed therein, are provided with novel means for presenting an air pocket in surrounding relationship to the motor shaft whenever the sewer line clogs up and the liquid contained in the housing of the machine is subjected to considerable pressures, the air in the pocket precluding passage of liquid and ground products from the housing through the shaft opening and onto the motor.

An additional important aim of the invention is to provide a garbage grinding machine having the features specified above wherein the structure presenting the air pocket communicates with the interior of the lower chamber of the grinder housing throughout an annular area disposed above the normal level of the liquid within the lower housing chamber, to thereby preclude passage of liquid and pulverized waste products outwardly from the housing through the shaft opening, the air contained in the pocket being compressed by the liquid within the housing and which is in turn under pressure by virtue of a blocking of the sewer pipe.

In the drawings:

FIG. 1 is a side elevational view of a machine for grinding waste products and embodying the concepts of the present invention, certain parts thereof being in vertical cross section to illustrate the details thereof; and

FIGS. 2 and 3 are horizontal, cross-sectional views taken on the lines 2-2 and 33 respectively of FIG. 1 and both looking downwardly in the direction of the arrows.

The garbage grinder broadly numerated 10 in the drawings and incorporating the features of the present invention, includes a main housing 12 having an upper section 14 and a lower section 16.

Section 14 has a cylindrical, central body 18 provided with a flange 20 adapted to be secured to a sink or the like to place body 18 into registering relationship with the sink opening. A flange 22 on body 18 is releasably connected to a cylindrical upper segment 24 of section 16. A plurality of stud bolts 26 releasably interconnect sections 14 and 16.

A lower, annular, transversely convex side wall 32 of section 16 is integral with segment 24, while a generally horizontal, transversely irregular bottom wall 34 of section 16 is integral with the lower margin wall 32. Downwa-rdly projecting, centrally disposed, tubular 'boss 36, integral with wall 34, is coaxial with shaft-clearing opening 38 in wall 34 and mounts a roller bearing 40 maintained in spaced relationship to the bottom face of wall 34 by a washer 41.

An electric motor 42 is secured to an annular flange 44 of section 16 at the zone of juncture of walls 32 and 34. Motor 42. has a shaft 46 projecting upwardly through opening 38. Shaft 46 has a lower section 48 of greater diameter than that of the inner race of bearing 40, a central portion 50 of the same diameter as the inner race of bearing 40 and an upper, externally threaded portion A rotor 54, removably secured to the portion 52 includes a horizontal body 56 having a central recess 58 receiving washer 60 positioned in overlying relationship to the portion 52. Boss portion 62 of rotor 54 depends from body 56, and a central bore 64 complementally receives portions 52 and 50 of shaft 46. A sleeve 66 is tight on portion 50 and interposed between boss portion 62 and the inner race of bearing 40. When rotor 54 is turned onto portion 52, sleeve 66 and the inner race of bearing 49 are clamped tightly against the upper end of section '48 before rotor 54 engages the upper end of portion 50. A look nut 68 on shaft 46 bears against washer 60.

Upright lugs 70 and 71, integral with the upper surface of body 56, serve to reduce the garbage and other waste products to relatively small particles by forcing the same against projections 74 on the inner face of a tubular insert 76 beneath flange 22 of section 14. An annular groove 78 in section 16 at the zone of juncture of segment 24 with side walls 32 complementally receives the outwardly projecting flange Stl of insert 76. The particles pass from insert '76 to section 16 defined by wall 3-2 through notches 79 in insert 76.

As best shown in FIG. 1, boss 62 of rotor 54 is conical in configuration, with the diameter thereof uniformly decreasing as the lower end of boss portion s2. is approached, and lower section 16 of housing 12 is provided with a tubular, internal section broadly numerated 82 and which includes a tubular, conically configured main body portion 84 integral with bottom Wall 34 in coaxial relationship to opening 38, and provided with an upper, annular flange portion 86 integral with the upper margin of main body portion 84. The upper surface $8 of flange portion 85 tapers downwardly as shown in FIG. 1, as the outer peripheral margin thereof is approached to prevent condensation from collecting on surface 88 during periods of non-operation of motor 42. The inner surface of section 32 is substantially complcrnental with the outer proximal surface of rotor 54, although all of such surfaces are in spaced relationship to prevent contact therebetween. In this respect, it is to be noted that the undersurface 9d of main body 56 of rotor 54 is also tapered to be complemental with the surface 83 of flange portion 86 of section 82.

A substantially cylindrical skirt 92 is integral with the lower surface '90 of body 56 of rotor 54, depends therefrom and is of a vertical dimension substantially equal to the height of main body portion 84 of section 82. It is to be noted that the upper part of skirt 592 is disposed in relatively close spaced relationship to the outer periphery of flange portion 86 and is concentric with section 82 as well as shaft 46.

Lower section 16 of housing 12 is adapted to be connected to a sewer line and in this respect, a conduit 94 extends through side Wall 32 in substantially tangential relationship thereto, terminating at its inner end in radial relationship to shaft 46.

The outer race of bearing as is fitted tightly within boss 36 and the inner race is tight on shaft 46. Bearings 49 of the type having the balls thereof embraced by opposed seals as shown, are readily available on the open market. Washer 41, overlapping both races around sleeve 66, provides additional precaution against moisture drainage to motor 42, particularly if the washer 41 is made from gasket material and clamped tightly in place between bearing 40 and the wall thereabove.

In operation, waste products to be ground are directed into housing 12 through the inlet defined by flange portion of upper section 14, whereby the materials gravitate onto the upper surface of rotor 54. It is to be understood that a constant supply of liquid such as water is directed into housing 12 in conjunction with the materials to be ground, and that motor '42 is energized to cause shaft 46 and thereby rotor 54- to be rotated. Lugs 74 reduce all of the garbage to particles small enough to pass into the chamber defined by annular wall 32 for ultimate passage to the sewer line via pipe 94.

In the event of clogging in the sewer line to which pipe 94 is connected, the water level in section 16 rises until it becomes coincident with the lower edge of skirt 92. However, such water will not rise appreciably within skirt 92, even though it backs up to the top of body 18 because of the air that is trapped in skirt 92 above the water.

Boss 62 and tubular section 82 are highly important to the protection of motor 42. Note that the Water must rise above the flange 86 before it can flow into body 84; in fact, since surface 88 slopes upwardly as boss 62 is approached, the water level must be virtually against surface '94} before the overflow into body 84 commences.

In practice however, the head of water in housing 12 is insuflicient toccmpress the air in skirt 92 and in body 84, enough to permit the water to rise as high as flange 86.

Another important factor is the appreciable small vollune of air in body 84 as compared with the volume of air in skirt )2 exteriorly of body 84. This simply means that all of the air in ski-rt 92 must be compressed into body $4 before water can drain thereinto and the water pressure is by no means that great.

Flange 86 also tends to deflect Water that may splash upwardly within skirt 92 as the latter continues to rotate, and while a meniscus may well form on the water in skirt 92, gravity and centrifugal force will prevent the water from climbing the inner surface of skirt 92 and flowing inwardly along surface 88.

It is also apparent from the foregoing that the tight fit of the inner race of bearing 40 around the motor shaft 46, and the tight fit of the outer race of bearing 40 within the element 36, prevents up and down movement of the shaft 46 as is quite common in machines of this type.

It can be appreciated further that the construction above described eliminates the need for the somewhat expensive, and yet unreliable seal that is normally used in garbage grinders of the character herein disclosed. Such conventional seals, provided as a sole, if not promary means of protecting the motor, wear quite rapidly and simply do not afford the protection that is needed.

The Washer 41 is not used nor needed as a holdback for the water; instead, it merely functions to trap the air thereabove and thereby prevent the liquids from entering the body 84. Very little, if any air will bleed past the washer 41 and the seals that are inherently provided in bearing 49 as shown notwithstanding the fact that a free-running fit must be provided between washer 41 and the collar or sleeve 66.

Having thus described the invention what is claimed as new and desired to be secured by Letters Patent is:

1. In a machine for grinding waste products, a housing having a waste products inlet, a waste products outlet disposed below said inlet in spaced relationship thereto and adapted to be coupled to a sewer pipe, an inner grinding surface intermediate said inlet and the outlet, and an opening therein for clearing a shaft; power means disposed exteriorly of the housing and provided with a shaft extending through said opening into the housing; and a rotor joined to the shaft for rotation therewith and having an outer grinding surface disposed to cooperate with said inner grinding surface of the housing to grind the products therebetween as the rotor is rotated and the products flushed through the housing by a flow of liquid directed thereinto through said inlet, said housing having a tubular section surrounding said shaft at the area thereof where the same projects outwardly from the housing through said opening, and said rotor having a cupshaped segment thereon, normally circumscribing said section of the housing, disposed in spaced relationship to said section and cooperating with the latter to present an annular air pocket surrounding the shaft whereby the air in said pocket precludes passage of the liquid and ground products from the housing through the opening and onto said power means, said section of the housing being substantially concentric with the opening, extending away therefrom, and being in spaced relationship to said shaft, said rotor being provided with a tubular boss thereon, receiving the shaft and extending into and spaced from said section to restrict the volume of the air pocket presented between the boss and said section.

2. A machine as set forth in claim 1 wherein said section includes a conical main body portion joined to the housing and an annular flange portion projecting outwardly from the marginal portion of said main body portion remote from the part of the housing to which said main body portion is joined, said flange portion being disposed in relatively close, spaced relationship to said rotor and terminating in relatively close, spaced relationship to said segment on the rotor.

3. In a machine for grinding waste products, a housing adapted to be disposed in an upright position and having a waste products inlet in the upper end thereof, an opening in the lower end thereof for clearing a shaft, a waste products outlet in the lower part of the housing spaced from said opening, and an inner, peripherally extending grinding surface intermediate the inlet and the outlet and concentric with said opening; power means below the housing and provided with an upright shaft extending through said opening into the housing; and a horizontally rotatable rotor joined to the upper extremity of the shaft for rotation with the latter and having an outer, peripherally disposed grinding surface in relatively close, spaced relationship to said inner grinding surface of the housing and adapted to cooperate with the same to grind the products therebetween as the rotor is rotated and the products flushed through the housing by a flow of liquid directed thereinto through the inlet, said housing having an upright section integral therewith within the same and including a substantially conical main body portion in spaced, surrounding relationship to the shaft and a generally horizontal, annular flange portion integral with the upper margin of said main body portion, projecting outwardly therefrom and concentric with said shaft, the rotor being provided with a depending, substantially conical boss portion extending downwardly into the main body portion of said section and spaced from the inner surface of said main body portion, and a cylindrical skirt depending from the rotor in surrounding relationship to said section and spaced from the outer peripheral edge of the flange portion of said section, said skirt, the boss on said rotor and the section cooperating to present an annular air pocket surrounding the shaft where the same extends outwardly from the housing through said opening whereby the air in said pocket prevents liquid and ground products from passing from the housing through said opening and onto the power means.

4. A machine as set forth in claim 3 wherein said skirt extends downwardly a distance substantially equal to the height of said main body portion of said section of the housing.

5. A machine as set forth in claim 3 wherein the upper annular surface of said flange portion of the section is inclined downwardly from the proximal peripheral margin of the main body portion of the section to prevent collection of condensation on said upper annular surface of said flange portion.

6. A machine as set forth in claim 3 wherein the undersurface of said rotor normally proximal to said flange portion of the section is in substantially uniformly spaced relationship thereto and complementally configured therewith.

7. A machine as set forth in claim 3 wherein said rotor is removably connected to the shaft to permit ready cleaning of said section, the boss and said skirt of the rotor.

8. In a garbage grinder, a housing adapted to receive a body of water; a rotor in the housing; a motor beneath the bottom of the housing and provided with a shaft extending upwardly therefrom through said bottom of the housing and operably coupled with the rotor; and structure for preventing flow of water from the housing to the motor, said structure including an air seal between the shaft and the bottom of the housing at the zone of passage of the shaft therethrough, a continuous skirt in the housing above said bottom and secured to the rotor in depending relationship thereto, said skirt surrounding the shaft in spaced relationship to the latter, said bottom having a tubular portion extending upwardly therefrom in the housing around the shaft and terminating at its uppermost end in an outturned flange adjacent the rotor therebeneath; presenting a space between the top of the flange and the bottom of the rotor whereby said space and the tubular portion form an air trap above the air seal, the skirt surrounding the periphery of the flange.

9. The invention of claim 8, the flange and said bottom of the rotor sloping downwardly as the skirt is approached thereby.

10. The invention of claim 8, the skirt being cylindrical and the flange having an annular periphery in juxtaposition to the inner face of the skirt.

11. The invention of claim 8, the rotor having an integral boss depending therefrom around the shaft within the tubular portion and spaced therefrom.

12. The invention of claim 11, the tubular portion and the boss being frusto-conical, progressively increasing in diameter as the rotor is approached.

References Cited in the file of this patent UNITED STATES PATENTS 2,601,731 Trede July 1, 1952 2,853,249 Wilder Sept. 23, 1958 2,970,777 Hardy et a1 Feb. 7, 1961 

